Apparatus for molding concrete septic tanks



061;. 31, 1950 E, FRY ET AL 2,527,717

APPARATUS FOR MOLDING CONCRETE SEPTIC TANKS Filed Sept. 6, 1949 5 Sheets-Sheet l INVENTORS ELWOOD Fax HENRY FASENMYEP- I BY Tgrl a fi@ Oct. 31, 1950 E. FRY ET AL 2,527,717

APPARATUS FOR MOLDING CONCRETE SEPTIOTANKS Filed Sept. 6. 1949 5 Sheets-Sheet 2 JNVENTORS 3 ELWOOD FR! @2 Hemav FASENMYER Oct. 31, 1950 E. FRY ET AL 2,527,717

APPARATUS FOR MOLDING CONCRETE SEPTIC TANKS Filed se i. 6, 1949 :s Sheets-Sheet 5 4 INVENTORS /57 ELWOOD FRY @2 HENRY FAEENMYER Patented Oct. 31, 1950 NT oFFIcE APPARATUS FOR MOLDING CONCRETE SEPTIC TANKS Elwood Fry and Henry Fasenmyer, Warren, Pa.

Application September 6, 1949, Serial No. 114,148

2 Claims.

This invention relates to apparatus for manufacturing concrete tanks, and more particularly for manufacturing tanks of large size, such as septic tanks. I

It is among the objects of the invention to provide improved apparatus for rapidly and efilciently manufacturing the tank parts, which apparatus is effective to cast one end wall and substantially one-half of the side wall of a cylindrical tank integrally in one operation, and to tamp the concrete material of the tank walls to a firm and strong condition, which produces tanks of uniform size, shape and strength without voids or holes in the walls thereof, and'which is simple and durable in construction, economical to manufacture and operate, and easy to separate from the tank parts manufactured thereby.

Other objects and advantages will become apparent from a consideration of the following de-- scription and the appended claims in conjunction with the accompanying drawings, wherein:

Figure l is a front elevation of tank-forming apparatus illustrative of the invention, certain parts being broken away and shown in crosssection to :better illustrate the construction thereof;

Figure 2 is a side elevation of the tank-forming apparatus illustrated in Figure l, certain parts being broken away and shown in crosssection to better illustrate the construction thereof;

Figure 3 is a transverse cross-section on the line 33 of Figure -1, certain parts being broken away to better illustrate the construction of the apparatus;

Figure 4 is a cross-sectional view on the line 4-4 of Figure 3;

Figure 5 is a cross-sectional view on the line 55 of Figure 4;

Figure 6 is a cross-sectional view on the, line longitudinal, medial plane.

With continued reference to the drawings, the numeral [0 indicates apitprovided-below a floor VII and surrounded by a wall 112 and having a bottom wall 13.

.A reduction gear unit 14 is mounted ,on the bottom wall of the pit and has one shaft 15 directed vertically upward, and a second shaftflfi directed horizontally. A suitable power unit, such as an electric motor 17, is connected to the horizontal shaft IE to drive the vertical shaft [:5 at a reduced speed. A cylindrical housing l8 rests on the bottom wall l3 of the pit and encloses the-reduction gear unit l4 and partly encloses the motor II. This housing has a top cover I!) provided with a central aperture in which is mounted a bearing bushing 2|]. Radial ribs 2| are provided at the lower side of the cover [9, and converge toward the center of the housing to a cylindrical sleeve 22 which also receives the bushing 20. A spider structure is disposed below the cover I9 and iiicludes radial ribs 23 which converge from the cylindrical wall of the housing to a bearing sleeve 24 which receives a second bearing bushing 25 in vertical alignment with the bushing 20. A shaft 26 is journaled in the bushings 20 and 25, and is connected at its bottom end to the vertical shaft I 5 of the reduction gear unit l4-by a flexible coupling 21 of any wellknown construction. A spider structure 28 is disposed above the housing top [9, and comprises a plurality of radially-disposed ribs 29 which converge to a central sleeve 30 which receives and is rigidlysecured to the shaft 25 at the upper end of the shaft projecting above the top cover IQ of the housing l8. A circular table 3| is mounted on the spider structure 28 for rotation by the shaft 26, and the table is also supported by this shaft. An annular cover 32 overlies the upper end of the pit ll] around the table 3|, and extends from the edge of the floor ll substantially to the periphery .of the table.

A cylindrical outer form, generally indicated at 33, is mounted on the table 3! concentrically therewith. A plurality of angularly spacedapart pads 3 are mounted on the table plate 3*] and provided respectively with upstanding lugs 35 positioned at the outer circumference of the table for engaging and rotating the outer form 33. The two semi-circular parts of a diametrically-split circular ring 36 are secured to the two semi-cylindrical parts of the-cylindrical wall 37 of the outer form 33 respectively to constitute a reinforcing flange for the bottom end of the outer form. The two parts of the wall 31 are secured together at opposite-sides of the forrnby a plurality of manually-releasable locks 38 and 39, so that the two halves of the .form side wall can be separated to strip the form from a cast therein. .After a tank half is cast, the outer form with the cast tank half therein is lifted f om the ta le n pl ced on th i po with the bottom plate 4| resting on floor supports. The locks 38 and 39 are then released and the halves of the outer form separated and removed from the casting, the bottom plate remaining under the casting as a pallet. The two parts of the outer form are then returned to the table and re-assembled with a new bottom plate. At its upper end, the outer form '33 is surrounded by an external flange 40 in the form of a diametricallysplit ring which reinforces the side wall parts at their upper edges.

The bottom plate 4| of the outer form is marginally supported in the outer form by lugs 4 and is provided with a. central aperture which receives a guide pin 42 welded at its lower end to table plate 3| at the center of the latter.

The inner form 43 is a cylindrical drum having a side wall 44 of an external radius less than the internal radius of the side wall of the outer form by the thickness of the tank to-be cast in thelapparatus, This inner form has a bottom wall pr plate 45 marginally secured to the side wall 4'4 at the bottom edge of the latten'and a top wall. orplate 4G marginally secured to the side wall 44 at the top edge of the latter. A tubular posti! is concentrically disposed within the cylindrical inner form, and extends at its upper end'through a central aperture provided ,in-the top plate 450i this form. At its lower end :the post 47 is secured to the bottom plate t surrounding the-aperture through which the guide pin 42 extends; and a bearing bushing 48 is .mounted in a counterbore provided in the post 41 atits lower-end, the pin 42 being journaled in this-bushing.

.-; A spider structure is disposed within the inner form; and comprises legs or'ribs i9 which extend radially from the side wall M of the inner :form to the center post 41 intermediate the height of the inner form to internally reinforce this inner form.

An air -conduit50 extends through the top wall 46 of the inner form and has within the inner form a right-angle formation, so that its opposite .endabuts and is secured to the center post 47. 'An aperture 5| in the center post leads from the .conduit 50 to the interior of the center post, and a bore 52 in the guide pin 42 extends from the top of the guide pin to the side of the guide pin at a location adjacent the bottom end of the bearing bushing 8,so thatair will be admitted under the bottom wall 45 of the inner form when the inner'form is lifted out of a tank' part cast between the inner and outer forms, to prevent the creation of a vacuum between the bottom of the inner form and the tank end wall.

Two elongated, vertically-disposed posts 53 and 54 are mounted, with their bottom ends on the top of the pit wall l2, and are respectively disposed at diametrically-opposite sides of the pit.

A top beam 55 extends between the posts 53 and and is secured at its opposite ends respectively to these posts at the upper ends thereof. A hydraulic cylinder 56 is secured at one end to the beam 55 at the mid-length location of the latter, and suitable hydraulic conduits it? and I88 are connected to this cylinder to supply hydraulic fluid under pressure to the cylinder and provide a return line therefor. A piston, not illustrated, is reciprocable in the cylinder 56, and a piston rod 51 xtends from the bottom end of the cylinder and is received at its lower end in the upper end of the center post 4? of the inner form 43. This piston rod 51 is rigidly secured in the center post 41, so that the inner form can. be

'33 and 43.

raised to a position in which it is entirely above the outer form 33 by the application of hydraulic fluid under pressure to the lower end of the hydraulic cylinder 56.

An intermediate beam 58 extends between the posts 53 and 54 and is secured at its opposite ends to the posts 53 and 54, respectively, intermediate the length of the latter. At its midlength location this intermediate beam carries a sleeve 59 within which is mounted a bearing bushing in which the piston rod or shaft 51 is slidably received.

A guide beam 6| is secured, at its mid-length location, to the piston rod 51 immediately above the top of the inner form 43, and extends between the two posts 53 and 54. The post 53 is provided, on its inner side, with an elongated guide rib 62, and the post 54 is provided with a similar ri-b 63. The beam 6| is provided, at its opposite ends, with channel-shaped guide shoes 64 and 65 which slidablly engage the guide ribs 52 and 53, respectively, to guide the beam 6! in its vertical movements incident to the vertical movements of the piston rod 5| by the hydraulic device 55. 1-

Two tamping devices, as generally indicated at 65 and 61, are mounted on the beam 6| at respectively opposite sides of the piston rod 5|, and are effective to tamp concrete deposited between the side walls of the inner and outer forms As both of these tamping' devices are similar in construction and o eration, and as they are of construction already known to the artga brief description of only one is considered sufficient for the purposes of the present disclosure.

The tam ing device 61 has been selected for detailed description, and comprises an electric motor 58 mounted on the top plate 69 of the guide beam 6| bya base structure 10. The motor shaft extends from one end of the motor 68 and carries a series of V-belt pulleys H. A shaft 12 is journaled ina bearing block 13 mounted on the top plate 69 and carries, on one end, a series of V-belt pulleys 14, one of which is connected by a V-belt to a corresponding pulley of the group H. A disc 15 is concentrically mounted on the opposite end of the shaft 12, and is disposed beyond the longitudinal edge of the top plate 69; A U-shaped guide structure l6 is journaled adjacent its midlength location on the shaft 12 at the inner side of the disc 15 and carries, at its respectively opposite ends, two guide sleeves Tl and T8 in which a plunger rod 19 is reciprocably mounted. The plunger shaft or bar 19 carries a pestle on its lower end, which pestle operates in the space between the side walls of the inner and outer forms to tamp the concrete mix deposited into this space. A clamp 8| surrounds the plunger 19 between the guide sleeves l1 and 18, and is connected by a link rod 82 to the disc 15 eccentrically of the disc, so that the tamp rodor plunger will be reciprocated vertically when the disc rotates. The clamp 8| has a frictional connection only withthe plunger rod '19, so that as the concrete is-gradually filled into the space between the inner and outer forms, the'pestle 80 will be permitted to rise automatically and continue its tamping operation.

In the operation of the device and in the manufacture of a bottom part of a septic tank, with the inner form elevated above the outer form, a quantity of relatively dry concrete mix is deposited in the outer form sufficient to form the batten; a l I the tank. The inner'form is th n lowered into the outer. forn1*.-;iintil-:'stop 651 on rod Elcontacts 'the top of ,beamfi l ,-.thereby properly positioningtheinner form-'1 inthe, outerv form. The motor .I l .is ;then .placed in operation to "rotate the table AI and theputer form 33,- the inner form .43 remaining stationary. Dry-concrete mix is .thendeposited into the jspacebetween the Slde wallsof theinner and :outenforms by means of a suitable chute or 'chutes,.not illustrated, and this mix is ffirnily .tampedas it is'r'otated -by;the outer form. This rotation of the ;outer form :relative to the. inner sform,.imposes ja certain amount of centrifugal force on the concrete mix on/the .bottom plate. of the-outer form,and also as the concrete mix is .tampe'd to a substantially solid condition.

As soon as .the space. between the sidewalls of the inner andoutersforms hasbeen filled, the

operation of the tamping devices "is discontinued and the top edge of the concrete body is dressed off and then roughened with a wire brush or other suitable means. The operation of motor I! is then discontinued and the hydraulic device 56 placed in operation to move the inner form out of the cast tank part and to a position entirely above the outer form. The outer form with the tank casting therein is then removed from the table 28 and placed on the floor, after which the two halves of the side wall of the outer form are separated by releasing the locks 38 and 39 and pulling the two parts of the form side wall apart. After the outer form has been removed, it is returned to the table for further use, the bottom plate 4| being used as a pallet for supporting the cast body.

In manufacturing the top halves of septic tanks, the process is exactly the same as that described above, except that certain plugs or spacers are placed between the inner and outer forms to provide the manhole opening at the center of the top wall of the tank, and the pipe-connection openings in the side wall of the tank near the top end thereof.

As particularly illustrated in Figure 4, a fiat ring 95 of somewhat truncated, conical shape is placed between the bottom plates of the inner and outer forms. This ring has, at its center, a sleeve 85 which receives the guide pin 42, and is secured to the ring by a plurality of angularly spaced-apart spokes 81. This ring 85 is placed on the bottom plate 4| of the outer form before the concrete to provide the top end wall of the tank is placed on this bottom plate with its sleeve 86 receiving the guide pin 42 to center the ring relative to the outer and inner forms.

Two circular plugs 88 and 89 which are also preferably of somewhat truncated, conical shape, are secured to the side wall of the outer form at the inner side of the latter, and at a location slightly spaced from the bottom plate 4!. These plugs are detachably secured to the side wall of the outerform by suitable means, such as the bolts 99 and 9|, and the wing nuts 92 and 93, and have a thickness substantially equal to the distance between the side walls of the inner and outer forms. The top half of the tank i-scast in '90 and 9|, and that after the :formflhas been stripped, the plugs 88 and 89 and the ring -can be knocked out of the cast tan-k part and rejplaced'qbetween the forms in the manner indicated above.

The bottom and top halves of the tanks'can be torm'ed at-difierent times on the same machine, or can be formed on two different ma- .wchines if desired. When a sufiicient'number of tank parts have been formed, :they are then assembled to {,DI'OVldB the complete tanks. First, the hole '94 in the "bottom 'wall l of the bottom half .96-of'the tank, ;,providedby the guide pin 42, .is filled with concrete 'by hand, and any small *Voids'or cracks in the inner surfaces of the two tank parts'are also filled by hand, and smoothed :o'ut. Semi-cylindrical bafiles, not illustrated, are then installed over, the sideopenings in the top part of the ;tank by cementing them in place with :a concrete mortar, and .a layer of mortar is then placed on the top edge of the lower tank part. The upper part of the tank is then placed in position on the lower tank part, and the motar placed between the roughened, adjacent edges of the two parts allowed to set up to firmly secure the two parts of the tank together in operative assembly. The tank is then ready for installation.

It will be noted that the entire tank is cast without the use of reinforcement of any kind and that the end walls are cast integrally with the side walls of the two parts, providing an extremely strong and rigid construction. By casting the tank in two separate halves, a large tank can be provided without using such quantities of concrete as would render the castings difficult to handle, or unduly heavy.

The invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiment is, therefore, to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are, therefore, intended to be embraced therein.

What is claimed is:

1. Apparatus for manufacturing cylindrical concrete tanks comprising a rotatable table supported at floor level, means below said table supporting and rotating the same, a cylindrical outer form mounted on said table, a fixed structure extending above said outer form, an inner cylindrical form movable into and out of said outer form, and means carried by said fixed structure and connected to said inner form for moving the latter between a position in which it is operatively disposed within said outer form and a position in which it is disposed entirely above said outer form, said inner form comprising a cylindrical side wall having a radius less than the radius of the side wall of said outer form by the wall thickness of a tank part to be cast between said forms, a top plate and a bottom plate se- "cured to said cylindrical side wall at respectively opposite ends thereof, and a tubular center post extending concentrically through the space between said top and bottom Walls, a guide pin secured to and projecting upwardly from said table rotatably received in said center post, said guide pin having a bore extending from its upper end to the side thereof adjacent said bottom wall, said center post having an aperture therein communicating with the bore in said guide pin, and a tubular air conduit extending from said aperture through said top wall.

Apparatus for manufacturing cylindrical concrete tanks comprising a rotatable table supported at iioor level, means below said table supporting and rotating the same, a cylindrical outer j form mounted on said table, a fixed structure extending above said outer form, an inner cylindrical form movable into and out of said outer form, and means carried by said fixed structure and connected to said inner form for moving the latter between a position in which it is operatively disposed within said outer form and a position in which it is disposed entirely above said outer form, said inner form comprising a cylindrical' sidewall having a radius less than the radius of the sidewall of said outer form by the wall thickness of a tank part to be cast between said forms, a, top plate and a bottom plate secured to s'aidcylindrical side wall at respectively opposite ends thereof, a tubular center post extending concentrically through the space between said top and bottom walls, a guide pin secured to and projecting upwardly from said table rotatably received in said center post, said guide pin having a bore extending from its upper end to the side thereof adjacent said bottom wall, said center post having an aperture therein communicating with the bore in said guide pin, and a tubular air conduit extending from said aperture through said top wall, and alift rod for said inner form secured at its lower end to said center post at the upper end of the latter and extending above said forms.

ELWOOD FRY.

HENRY FASENMYER.

' REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Tankovich Sept. 27, 1949 

